• Ei tuloksia

The empirical results indicate that the spot and future prices of used commodities are stationary after the first differencing but the spot and future price of natural gas had the stationarity even before doing the first differencing.

The major findings of the study are as follows:

The Johansen cointegration test exhibits that that there exist the long run relationship between the spot and future prices of the agricultural, energy and precious metals (commodities) except the crude oil spot and future prices.

Thus, the first hypothesis is fulfilled.

The granger causality test exhibits the bi-directional, uni-directional and no causality relationship between the selected spot-future, future-spot, spot-spot and future-future prices of the commodities. In the case of agricultural commodities (cocoa and coffee), energy (crude oil) and precious metal (gold) bi-directional relationship was found whereas at the same time natural gas spot and silver future have the uni-directional relationship with the natural gas future price and silver spot price respectively. Thus, it is safely concluded that although in the theories future prices play a crucial role in the price discovery process, the spot price too play an equal role in this respect. In this way, the second hypothesis is also explained and fulfilled with the notion that prices of one variable granger causes the price of another variable.

Finally, the VAR model explained the interrelationship among the prices of the variables in the system when the shocks are given. It highlights the fact that the movement in the dependent variable occurs which is caused due to its own shock. Moreover, the VAR model results the proportion of effect is high in the case of the respective spot and future of the commodities rather than among the prices of the commodities meaning the changes of movement is seen between the spot vs. spot, future vs. future, spot vs. future or future vs.

spot prices of the same commodity. Here, the third hypothesis is also satisfied.

From the above results, it is found out that the differences in the relative importance of the spot and future prices in the price discovery role in the financial markets for the energy and agricultural commodities including precious metals. Moreover, it is important to understand and investigate the price discovery process of both the spot and future markets so as to guide and help the policy makers and market participants to formulate the efficient policies and improve the efficiencies of both markets. Moreover, the commodities like crude oil, natural gas, gold and silver have an important role in the spot and future market since they are the globally traded commodities with high risks thus raising the importance of the use of derivatives. Likewise, price fluctuations of the commodities directly impact on the personal life of everyone plays a vital role in the economy of the country should be realized.

Masih and Masih (2002) suggested that in the presence of either a non-stationary risk premium or a non-non-stationary convenience yield there exists no cointegration of commodity markets. Thus, from this point of view we can explain that for all the commodities (cocoa, coffee, natural gas, gold and silver) except crude oil there is the presence of the properties of the convenience yield and risk premium.

Similarly, the idea can also be generated that geopolitical plays a vital role in the spot and future markets which can completely twirled out the market scenario in a blink.

In addition, this study could be furthermore extended to observe the situation of spot and future prices of other major commodities focusing on the emerging markets since, these markets hugely affect the global business and comprise the huge space in the global market.

This paper will facilitate the academician, researchers, policy makers, financial analyst, and market players to know the actual value and forecast the outcomes of introduction the options in the global financial market. Moreover,

as Batra (2004) highlighted the fact that estimations of market volatility will help in this matter as it is considered as the barometer of the susceptibility of financial risks. Similarly, this paper will help portfolio managers in identifying the risks and hedge them by making efficient portfolios along with the portfolio diversification and creating arbitrage opportunities. If the company or an individual wants to utilize the new information on the movement of the future prices to enter in the hedging process, it is thus suggested to clearly overview the price movements or the relationships between the prices. Besides these, future contract is considered as one of the most important hedging instruments in a hedging contract since it highly reduces the business failure rates with making the availability of wide range of products in the financial markets. It has helped the companies to invest in resourceful but valuable production technologies and relocation of risks to those who are willing to bear and handle them (Culp, 2009). So as to reduce the spot price volatility future prices can be used in the financial market since the future market increases the overall market depth and in formativeness which are important for price discovery and transfer the risks.

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APPENDICES

APPENDIX 1.

UNIT ROOT TEST BEFORE FIRST DIFFERENCES I. Spot Prices

a. cocoa_spot

Null Hypothesis: COCOA_SPOT has a unit root Exogenous: Constant

Lag Length: 1 (Automatic - based on SIC, maxlag=14)

t-Statistic Prob.*

Augmented Dickey-Fuller test statistic -1.912965 0.3265 Test critical values: 1% level -3.432092

5% level -2.862195 10%level -2.567163

*MacKinnon (1996) one-sided p-values.

Augmented Dickey-Fuller Test Equation Dependent Variable: D(COCOA_SPOT) Method: Least Squares

Date: 01/28/13 Time: 15:29

Sample (adjusted): 3/03/2000 2/27/2013 Included observations: 3389 after adjustments

Variable Coefficient Std. Error t-Statistic Prob.

COCOA_SPOT(-1) -0.001911 0.000999 -1.912965 0.0558 D(COCOA_SPOT(-1)) -0.083416 0.017120 -4.872477 0.0000

C 4.286249 2.134546 2.008038 0.0447

R-squared 0.008160 Mean dependenvar 0.412842 Adjusted R squared 0.007574 S.D. dependent var 42.53885 S.E. of regression 42.37744 Akaike info criterion 10.33199 Sum squared resid 6080740. Schwarz criterion 10.33742 Log likelihood -17504.56 Hannan-Quincriter. 10.33393 F-statistic 13.92856 Durbin-Watson stat 1.998874 Prob(F-statistic) 0.000001

b. coffee_spot

Null Hypothesis: COFFEE_SPOT has a unit root Exogenous: Constant

Lag Length: 0 (Automatic - based on SIC, maxlag=14)

t-Statistic Prob.*

Augmented Dickey-Fuller test statistic -1.186958 0.6823 Test critical values: 1% level -3.432091

5% level -2.862195 10% level -2.567162

*MacKinnon (1996) one-sided p-values.

Augmented Dickey-Fuller Test Equation Dependent Variable: D(COFFEE_SPOT) Method: Least Squares

Date: 01/28/13 Time: 15:32

Sample (adjusted): 3/02/2000 2/27/2013 Included observations: 3390 after adjustments

Variable Coefficient Std. Error t-Statistic Prob.

COFFEE_SPOT(-1) -0.000863 0.000727 -1.186958 0.2353

C 0.001024 0.000905 1.130621 0.2583

R-squared 0.000416 Mean dependent var 6.49E-05 AdjustedRsquared 0.000121 S.D. dependent var 0.023817 S.E. of regression 0.023815 Akaike info criterion -4.636377 Sum squared resid 1.921587 Schwarz criterion -4.632761 Log likelihood 7860.659 HannanQuinncriter. -4.635084 F-statistic 1.408869 Durbin-Watson stat 1.964024 Prob(F-statistic) 0.235328

c. crude_oil_spot

Null Hypothesis: CRUDE_OIL_SPOT has a unit root Exogenous: Constant

Lag Length: 0 (Automatic - based on SIC, maxlag=14)

t-Statistic Prob.*

Augmented Dickey-Fuller test statistic -0.994072 0.7575

Test critical values: 1% level -3.432091 5% level -2.862195 10% level -2.567162

*MacKinnon (1996) one-sided p-values.

Augmented Dickey-Fuller Test Equation Dependent Variable: D(CRUDE_OIL_SPOT) Method: Least Squares

Date: 01/28/13 Time: 15:33

Sample (adjusted): 3/02/2000 2/27/2013 Included observations: 3390 after adjustments

Variable Coefficient Std. Error t-Statistic Prob.

CRUDE_OIL_SPOT(1) -0.000707 0.000711 -0.994072 0.3203

C 0.068410 0.049353 1.386121 0.1658

R-squared 0.000292 Mean dependent var 0.025006 Adjusted R-squared -0.000003 S.D. dependent var 1.339555 S.E. of regression 1.339557 Akaike info criterion 3.423145 Sum squared resid 6079.474 Schwarz criterion 3.426761 Log likelihood -5800.231 Hannan-Quinn criter. 3.424438 F-statistic 0.988179 Durbin-Watson stat 1.907600 Prob(F-statistic) 0.320259

d. gold_spot

Null Hypothesis: GOLD_SPOT has a unit root Exogenous: Constant

Lag Length: 0 (Automatic - based on SIC, maxlag=14)

t-Statistic Prob.*

Augmented Dickey-Fuller test statistic 0.397134 0.9829 Test critical values: 1% level -3.432091

5% level -2.862195 10%level -2.567162

*MacKinnon (1996) one-sided p-values.

Augmented Dickey-Fuller Test Equation Dependent Variable: D(GOLD_SPOT) Method: Least Squares

Date: 01/28/13 Time: 15:34

Sample (adjusted): 3/02/2000 2/27/2013 Included observations: 3390 after adjustments Variable Coefficient

Std.

Error t-Statistic Prob.

GOLD_SPOT(-1) 0.000157 0.000395 0.397134 0.6913

C 0.287616 0.348348 0.825657 0.4091

R-squared 0.000047 Mean dependent var 0.404546 Adjusted R-squared -0.000249 S.D. dependent var 10.83741 S.E. of regression 10.83876 Akaike info criterion 7.604724 Sum squared resid 398017.9 Schwarz criterion 7.608340 Log likelihood -12888.01 HannanQuinncriter. 7.606017 F-statistic 0.157715 Durbin-Watson stat 2.001814 Prob(F-statistic) 0.691294

e. nat_gas_spot

Null Hypothesis: NAT_GAS_SPOT has a unit root Exogenous: Constant

Lag Length: 13 (Automatic - based on SIC, maxlag=14)

t-Statistic Prob.*

Augmented Dickey-Fuller test statistic -8.622396 0.0000 Test critical values: 1% level -3.432099

5% level -2.862198

10% level -2.567164

*MacKinnon (1996) one-sided p-values.

Augmented Dickey-Fuller Test Equation Dependent Variable: D(NAT_GAS_SPOT) Method: Least Squares

Date: 01/28/13 Time: 15:34

Sample (adjusted): 3/21/2000 2/27/2013 Included observations: 3377 after adjustments

Variable Coefficient Std. Error t-Statistic Prob.

NAT_GAS_SPOT(-1) -0.308991 0.035836 -8.622396 0.0000 D(NAT_GAS_SPOT(-1)) -0.593655 0.037200 -15.95860 0.0000 D(NAT_GAS_SPOT(-2)) -0.514714 0.037896 -13.58220 0.0000

f. silver_spot

Null Hypothesis: SILVER_SPOT has a unit root Exogenous: Constant

Lag Length: 7 (Automatic - based on SIC, maxlag=14)

t-Statistic Prob.*

Augmented Dickey-Fuller test statistic -0.885676 0.7933 Test critical values: 1% level -3.432095

5% level -2.862197 10% level -2.567163

*MacKinnon (1996) one-sided p-values.

Augmented Dickey-Fuller Test Equation Dependent Variable: D(SILVER_SPOT) Method: Least Squares

Date: 01/28/13 Time: 15:35

Sample (adjusted): 3/13/2000 2/27/2013 Included observations: 3383 after adjustments

Variable Coefficient Std. Error t-Statistic Prob.

D(NAT_GAS_SPOT(-3)) -0.488060 0.038149 -12.79342 0.0000 D(NAT_GAS_SPOT(-4)) -0.460970 0.038167 -12.07786 0.0000 D(NAT_GAS_SPOT(-5)) -0.415108 0.037890 -10.95568 0.0000 D(NAT_GAS_SPOT(-6)) -0.366177 0.037297 -9.817898 0.0000 D(NAT_GAS_SPOT(-7)) -0.312400 0.036282 -8.610424 0.0000 D(NAT_GAS_SPOT(-8)) -0.260931 0.034780 -7.502397 0.0000 D(NAT_GAS_SPOT(-9)) -0.224427 0.032764 -6.849788 0.0000 D(NAT_GAS_SPOT(-10)) -0.174850 0.030193 -5.790992 0.0000 D(NAT_GAS_SPOT(-11)) -0.140264 0.027044 -5.186504 0.0000 D(NAT_GAS_SPOT(-12)) -0.114786 0.023132 -4.962177 0.0000 D(NAT_GAS_SPOT(-13)) -0.070513 0.017210 -4.097171 0.0000

C 810.0819 106.5830 7.600477 0.0000

R-squared 0.451412 Mean dependentvar 1.007243 Adjusted R-squared 0.449127 S.D. dependent var 3949.608 S.E. of regression 2931.430 Akaike info criterion 18.80880 Sum squared resid 2.89E+10 Schwarz criterion 18.83601 Log likelihood -31743.66 Hannan-Quincriter. 18.81853 F-statistic 197.6043 Durbin-Watson stat 2.003141 Prob(F-statistic) 0.000000

SILVER_SPOT(-1) -0.000699 0.000789 -0.885676 0.3759 D(SILVER_SPOT(-1)) -0.110491 0.017094 -6.463843 0.0000 D(SILVER_SPOT(-2)) -0.007372 0.017194 -0.428770 0.6681 D(SILVER_SPOT(-3)) -0.036938 0.017196 -2.148074 0.0318 D(SILVER_SPOT(-4)) 0.028862 0.017202 1.677840 0.0935 D(SILVER_SPOT(-5)) -0.007806 0.017196 -0.453965 0.6499 D(SILVER_SPOT(-6)) -0.024747 0.017196 -1.439122 0.1502 D(SILVER_SPOT(-7)) 0.123727 0.017112 7.230581 0.0000

C 0.016909 0.013144 1.286422 0.1984

R-squared 0.032045 Mean dependent var 0.007334 Adjusted R-squared 0.029750 S.D. dependent var 0.463550 S.E. of regression 0.456603 Akaike info criterion 1.272650 Sum squared resid 703.4313 Schwarz criterion 1.288949 Log likelihood -2143.687 Hannan-Quinn criter. 1.278477 F-statistic 13.96238 Durbin-Watson stat 1.997734 Prob(F-statistic) 0.000000

ii. Future Prices g. cocoa_fut

Null Hypothesis: COCOA_FUT has a unit root Exogenous: Constant

Lag Length: 0 (Automatic - based on SIC, maxlag=14)

t-Statistic Prob.*

Augmented Dickey-Fuller test statistic -1.974183 0.2985 Test critical values: 1% level -3.432091

5% level -2.862195 10% level -2.567162

*MacKinnon (1996) one-sided p-values.

Augmented Dickey-Fuller Test Equation Dependent Variable: D(COCOA_FUT) Method: Least Squares

Date: 01/28/13 Time: 15:37

Sample (adjusted): 1/04/2000 12/31/2012 Included observations: 3390 after adjustments

Variable Coefficient Std. Error t-Statistic Prob.

COCOA_FUT(-1) -0.001913 0.000969 -1.974183 0.0484

C 4.138859 2.011678 2.057416 0.0397

R-squared 0.001149 Mean dependent var 0.411209 Adjusted R-squared 0.000854 S.D. dependent var 40.42110

R-squared 0.001149 Mean dependent var 0.411209 Adjusted R-squared 0.000854 S.D. dependent var 40.42110